Aging and iodine loading of silver-functionalized aerogels

Conference · Mon Jul 01 04:00:00 EDT 2013

OSTI ID:22264194

Bruffey, S. H.; Jubin, R. T.; Anderson, K. K.; Walker, J. F. ^[1]

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1. Oak Ridge National Laboratory, P.O. Box 2008, MS-6223, Oak Ridge, TN 37831 (United States)

Engineered silver-functionalized silica aerogels are being investigated for their potential application in off-gas treatment at a used nuclear fuel reprocessing facility. Reprocessing will release several key volatile radionuclides, including iodine-129. To achieve regulatory compliance, iodine-129 must be removed from any off-gas stream prior to environmental discharge. Ag{sup 0}-functionalized aerogels have been demonstrated to have high iodine-capture capacity, high porosity, and potential for conversion into a waste form. Capture materials used in off-gas treatment may be exposed to a heated, high-humidity, acidic gas stream for months. Extended exposure to this stream could affect sorbent performance. It was the aim of this study to evaluate what impacts might be observed when Ag{sup 0}-functionalized aerogels prepared at Pacific Northwest National Laboratory were contacted with a dry air stream for up to 6 months and then used to adsorb iodine from a synthetic off-gas stream. Results demonstrate that there is some loss of iodine-capture capacity caused by aging, but that this loss is not as marked as for aging of more traditional iodine sorbents, such as silver-impregnated mordenite. Specifically, aging silver-functionalized aerogel under a dry air stream for up to 6 months can decrease its iodine capacity from 41 wt% to 32 wt%. (authors)

• Research Organization: American Nuclear Society, 555 North Kensington Avenue, La Grange Park, IL 60526 (United States)
• OSTI ID: 22264194
• Country of Publication: United States
• Language: English

Related Subjects

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS
AGING
GELS
IODINE 129
MORDENITE
NUCLEAR FUELS
POROSITY
REPROCESSING
SILICA
SILVER
VOLATILITY
WASTE FORMS